Delete the following directories (this insures all old files and settings are cleaned up):

C:\Windows\ActivePDF (note this will delete ALL legacy settings for ALL products)

C:\Program Files\ActivePDF\Server

C:\ProgramData\ActivePDF\APSMon

C:\ProgramData\ActivePDF\Logs\Server

C:\ProgramData\ActivePDF\Server

C:\ProgramData\ActivePDF\Settings\Server

Remove the following registry entries:

HKLM\SOFTWARE\ActivePDF (Legacy)

HKLM\SYSTEM\CurrentControlSet\Control\Print\Monitors\APSMon

HKLM\SYSTEM\CurrentControlSet\Control\Print\Printers\Server

HKLM\SYSTEM\CurrentControlSet\Control\Print\Printers\Legal

HKLM\SYSTEM\CurrentControlSet\Control\Print\Printers\StaticSample

Make sure all "ActivePDF Server" printers have been removed from your Devices and Printers

Download the latest version of Server.

Login to your server as a Local Admin to insure you have the necessary access.

Install Server normally.

These steps should ensure that all old files and registry entries have been removed. If you are installing using a local admin account, you will be able to properly recreate any entries needed to function properly.